Diaphragmatic sound-producer.



l. T. SlBLEY. DIAPHRAGMATIC vSOUND PRODUCER.

APPLICATION FILED SEPT. 5.1916.

Patent-@21r July 2,1918.

JAMES T. SIBLEY, F NEW YORK, N. Y.

yTo all 'whom t may concern:

f .l Be it known that I. JAMES T. Sumar, a citizen of the United States,and a resident of the borough of Manhattan, city, county,

M, mand State of New York, have invented cei'- tain new and usefulImprovements in Diaflphragmatic SoiindProdueers of which the`-.following is Va specification.

y wMy improvements are applicable to diam phragmatic sound producersgenerally, al-

Hthough shown herein as related more par- ,ticiilarlyto what are, knowntechnically as -..fSoiund-'boxes"v for use in connection with,"Lplionographs, important desiderata in the m .construction of whichare (l) the mounting ofthe stylus bar `or needle arm in such maiifyneras toi attain free and perfect articula- '.,tion thereof,Av whichinvolves the avoidance of dampening of sound by tightness of my]'mountand consequent frictional resistance;

(2) the construction and proportiouing l"Xofthe air chainbe` and throatplate back of the vibratory diaphragm in such manner as to attain aperfect quality of tone with a 4,25 `maximum volume 'of sound vibrationto be transmitted to the horn. fj, The invention consists in theconstruction and arrangement ofparts herein described .and` claimedspecifically, distinctive fea-` tures heilig the mounting of the yoke ofthe Y needle arm between V-edge -fulcrums and j" opposed 'rockable'members seated in conoavities having a prescribed relation to the apicesvof said V-edge fiilcrums, and in makving .the throat `:plateconstituting the back of the diaphrag'ma'tic air chamber adjustable lfjwith relation to said diaphragm, and in "forming it Withi marginalmeans of com? lfmunication with the` horn throat in `contra- ,.W.mlfdistinction to-central axial communication ftherewith asheretofore,the invention also Aincluding certain other details ofconstruction, all'for the purposes and reasons here l inafter more'fullyf set forth.

.45 In the accompanying drawings,

i Figure 1, is a front elevation of a pho- ;fnographic sound boxembodying the essen- ",Vtialfeatu'res of my invention;

I Fig. 2, is arear elevation thereof;

,i p0 Fig. 3, isa side' elevation thereof;

v l Fig. 4,` is a side elevation thereof taken at right angles to Fig.3, and looking toward the-needle` arm and mount l ;Fig. 5, is a centralvertical sectional ele- LISIS;iiation taken upon'iplane of line l5--5Fig.j1;

DIAPHRAGMATIC soUND-ier'ioniicnnh Specication otLetters Patent.

`Application. med September 5, 1916. Serial No. 118,333.

mount; i

.ing a relatively small mitted to the horn. y l' Patented July 2,191,8",y

Fig. 6, a like view showing the use lof adjustable throat plate; l

Fig. 7, is an elevation of the outer side of the anti-friction ballbearing plate;

Fig. 8, is an elevation of the inner yside of said anti-friction ballbeariii plate;

Fig. 9 is a sectionalidetail sizioiving vthe structiireot' the mount forthe needle arm yoke shown in prior figures of the drawings; Figs. l0,11, and 12, show modifications in .the form of roekable `member opposedto the V-shaped fulcriim Aof the needle `arm Fig. 13, is a trout Viewofthe throat plate shown in Fig. 5, detached from` the casing;

Fig. 14, is a rear view of the throat shown in Fig. 6.

In the drawings B, represents wliat:ina'y be designated as thev biielcorrbase of the sound box formed with the axial. so'cketb,

'for attachment to and communication with the throat of a horn` or othersoiind"delivery device. I), is the resilient diaphragm moiintedperipherally betweenaniiiilar gaskets g, g, preferably of tubularstructure as heretofore. The diaphragm I), and its gaskets y, g, areheld in place inl tliecasing b `the cap plate C, secured to the backplate liyi means of screws s, s. 1

Interposed between the diaphragm D, and

the back plate. B, is` the'throat plate'lT,

forming between it and the inner sideuof the diaphragm the airclia'inberc. Heretofore the' diaphragm D, has beenA partitioned oil'from thebase B, bya plateliaving a central aperture concentric with'thecen.

ter of the diaphragm and of relatively large area coincident with thearea ol greatest amplitude ot vibratory movement of said diaphragm. As aconsequence tlie main volume of air in the chamber a, has been `inertand';

uniitilized in an economic sense, practically all the. work of the.diaphragm havinggbeen expended in alternately pulling and )ushqiiantityo air through said central opening, so tliatthezf full value ofdiaphragiiiatie vibration .was not attained and utilized fortransmission to the horn. In other wordstli'e .air in a large annularmarginal area iii the diaphragm chamber surrounding said central-,if

opening in the throat plate was practically undisturbed and inactive,limiting and iin` pairing the tone and volume of sound transiIobyiatethis difficulty by so forming mythroat plate T, that provision ismade only' for marginal communication 'between' theV air chamber a, andthe throat chamber which opens into the passage to the horn. Ittwill beconceded of course that the extent of ivibration of the portion of theresilientdiaphragm D, immediately adjacent to its y g peripheral supportbetween'the annular gaskets g, g, is essentiallym'l and of little -ornovaccount in'afectinlgI the air in the diaphragm chamber a.

' the communicating space t, between the 'diaphragmatic air chamber a,and the throat chamber b', at the margin of the throat plate T, andbetween it and the peripheral support of the diaphragm D, I obviouslyattain the maximum effect of diaphragmatic vibration on the air in saiddiaphragmatic chamber a, vso that practically the whole Volume of air`contained therein is utilized` 'mau'gmenting and intensifying the soundWaves and transmitting them. to the horn,- the'closed central area of mythroat plate T, being directly opposed to the area of maximum extent ofVibration of the diaphragm D, asy,will be seen more particularly byreference'to Figs. 5, and 6, with the re- I the diaphragm sult that allliuctuations of pressurecreated by alternate rarefactions andcondensation of 'such air are' communicated withA full force to and.through the throat chamber 12'. v i

Obviously the communicating space t, may consist of a singleannularmarginal apertureas in Fig.' 6, in which the/throat plate is in the formof a centrally supported disk (shown in detail in Fig. 14) or of aplurality 0f marginal openings as in 'Figs 5,

and `13, concentric with the center of the plate and diaphragm, theedges of the throat plate being in this arrangement secured 4between the1base,`B, and the cap` C, by the 4screws s, s, ,hereinbefore referredto'.

The advantage of the' disk form ofthroat plate shown in Figs. 6, and.14, is that pro Vision is thereby made iwhereby the area or capacityofifthe air chamber a, may be regulatedwith fiaccuracy to meet the exactre` viouslybe effected bythe use of mechanical expedients of differentkinds and I do not limit myself in this respect, although the. 'meansshown in Fig; 6, is simpley and effective, consisting in providing therear side of the throat disk or plate T, with a screw stud` t', whichengages a female thread in ence by I positioning the spider web' Z22,`in the base. B,a set nut b3, also being providedby Imeans of which.

the throat plate T, may be secured infa pre-` scribed position withrelation' to the dia-l phragm D, as found most expedient by test.

In this diskstructure of throat plateT,

shown in Figs. 6, and 14, an annular plate e, is interposed between thecap C, and the base B, for the support of thc gaskets-g, g, anddiaphragm D.".In the structure shown in Fig. 5, the edge of the throatplate T,

performs alike function. e', is an annular` transmission metallically asfar as possible of mechanical Vibration `(as the scratching of theneedle) through the structurexand cushion or gasket interposed betweenthe` base B,and the other parts to prevent the` for a like reason rubberor similar washers l s', s are interposed between theA heads of thescrews s, s, and the back plate B. i From what has heretofore been saidin.

tion between the diaphragmati'c-air chamber connection'with the` meansof communica f a, and the throat chamber b', it .will be unf y derstoodthat by the ,use` of the term mar.-

ginal communication7 herein 'I mean to i,

designate any opening or openings in or..`

4created by the throat plate that will answer the purpose incontra-distinction to a throat y platewith a central aperture `asheretofore.

The yoke n, of the stylusor needle arm 1v N, is pivotally -supported ina `peculiar manner, z'. e., between one or more" member 1', directlyopposed, in its? contactual fixedl V-i shaped `knife edged fulcrums f,:and an ops7 a. posed rockable memberor members 7", confa cavely seated.By thefuse of the rockable engagement withthe yoke u, toA the apex ofthe V-shaped knife `edged fulcrum ffl `attain free and untrammeledarticulationv for the needle arm with a minimum of frictionalresistance, since vit is obvious that` ytheysaid 1. y rocking member 7',while coniiningthe yoke n, adequately againstfthe `Vshaped `knife edgeof the fulcrum,7will adapt itself readily ,tc the `vibratory motion ofthe needle arm;`

andl yoke without variation of pressure y i against said fulcrum point.I .thus obviate the muffiing of Vvibration `incidental to 'a tight mountand `the rattling and'slurri'ng` incidental to a loose mount, as is api;to` occur where spring; or trunnion mounts are employed as heretofore,in yboth of Whichfk types of molint very careful assembling and.

adjustment of. parts is necessary'in order to attain fair results,whereas by my type of mount the parts'may be assembled without I theuseof skilled labor since therelation `of sure is necessary. i

"*While in a pre the `parts 'is positivelypredeterminfed and fixed, andno adJustment of ytension or pres?.`

an anti-friction roller is used as the rockablel member r, asillustrated 1in sectional detail in Fig.- 9, still I do not limit myselfthereto,

ndr t anyispecifie form of rockable member,

since the modifications thereof shown in Figs. 10,k l1, and 12, orothers, may be sub- Stituted with like res'ult,-the rocker 1', in eachcase bein provided with a concave scat r', diametrica ly opposed to. theV-shaped knife edge of the` fulcrum. f Y

lBypreference two V-shapedknife edge 4 fulcrums f, are provided, one foreach arm of the yoke n, and 'the opposed rockable members r, are lseatedin concavities fr',

formed for their reception in a common bearing plate r2, secured rigidlyto the cap C, by, screws 1', r3, as shown more particularly in Fig. 4.The slots in the plate fr, through which the Shanks of the said screws14"", r3, pass may be made concentric to a medial point (as shown inFigs. 7, and 8) so that the rocker plate r2, may be so adjusted as to'impart a slight torsional strain to the 'needle bar N, if desired, forthe purpose of l stilieningA the diaphragm or action.

What I claim as lmy invention and desire .to secure by Letters Patentis,

1. In diaphragmatie sound producing apparatus of the characterdesignated, the com- Abina'tion with the diaphragm and its casing fofa'needle arm mount comprising two stai eof'ltonm'y 'V-Shaped fulcrums,opposed rockble members contacting with the needle f "aerm in alinementwith the apices of said 4fulerumsY a bearln plate formed with concaveseats for rockable members, and Ameans yfor adjusting said bearing plateon an-axis medial between said stationary V- `shaped fulcrums for thepurpose of imparting a torsional strain to the needle arm and diaphragmas set forth.

2. In diaphragmatic sound producing apparatus of the characterdesignated, the combination with the diaphragm and its casing of aneedle arm mount comprising two stationary V-shaped knife-edgedfulcrums, op-

posed anti-friction rollers contacting with from the casing, anddiametrieally opposed rockable members contacting with the needle arm 1nalmement with the apices ot said protnberant V-shaped knife-edgedfulcrums,

a rigid bearing plate ixedly attached to the casmg and provided with aconcavity, said rockahle member heilig movably mounted to imparttorsional strani to the needle bar and being seated in said eoncavity insaid rigid bearing plate, for the purpose set forth.

JAMES T. SIBLE Y.

Witnesses Dono'rmr MlA'rr,

Gao. WM. MIA'rr.

